LED Color Fade Effect

Sat, 31 Oct 2009 06:06:51 +0000

This is the circuit of LED color fade effect. Just like the name of the circuit, the light intensity of LEDs in this circuit will fade from high? intensity to low intensity and then off.

Here the final result preview:

30 uF condensator and the resistor marked with blue 100k control the speed of the fading. You can replace the 100 kilo ohm resistor with 100k linear potentiometer so you can adjust the speed any time. The supply voltage is 5VDC, you may use battery or power supply adapter to operate this LED color fade effect circuit.

You can make the circuit even simplier by leaving out other of the transistors and those leds that are connected to it. Good for power led pulsing etc.

LM324 is an OP-Amp amplifier. There 4 op amp, and we just use 2 op amp in above circuit diagram. You may use the other 2 op-amp to build another similar circuit. Transistor is BC547 and the led is ultra bright red with 220 ohm resistor in series.

Source: http://metku.net/colorfade/index_eng.html

The post LED Color Fade Effect first appeared on Electronic Schematic Diagram.

Running LEDs

Mon, 21 Sep 2009 00:47:45 +0000

This is running LEDs circuit which use timer ID NE555N and logic IC 4017N. IC 555 act as a multivibrator and generate frequency to be used for 4017 clock input.

The 4017 is a high speed silicon gate CMOS 5-stage Johnson counter with 10 decoded outputs. Each of the decoded outputs is normally low and sequentially goes high on the low to high transition clock period of the 10 clock period cycle. The CARRY (TC) output transitions low to high after OUTPUT 10 goes from high to low, and can be used in conjunction with the CLOCK ENABLE (CE) to cascade several stages. The CLOCK ENABLE input disables counting when in the high state. A RESET (MR) input is also provided which when taken high sets all the decoded outputs, except “0”, low.

R2 is a linear potensiometer to adjust clock frequency and of course the frequency of the blinking LEDs as well.

fun circuit | Electronic Schematic Diagram

LED Color Fade Effect

Running LEDs

CD74HC4017 Datasheet